Self aligning combustor and transition structure for a gas turbine

ABSTRACT

Gas turbine combustion apparatus in which the combustor is anchored at its upstream end and the transition member is anchored at its downstream end, the downstream end of the combustor and the upstream end of the transition member being disposed in mutual engagement and alignment and freely slidable relation during thermal expansion by a clevis support structure and sealed at their engaging portions by a slotted twin layer cuff spring.

United States Patent 1191 Scalzo et a1.

1451 Sept. 18, 1973 [54] SELF ALIGNING COMBUSTOR AND 3,609,968 10/1971 Mierley et a1 60/3932 TRANSITION STRUCTURE FOR A GAS 2,592,060 4/1952 Oulianoff 60/3932 TURBINE 2,774,618 12/1956 Alderson 285/302 X 2,494,659 1/1950 Huyton 60/3932 UX [75] Inventors: Augustine J. Scalzo, Philadelphia;

Leroy McLaurm Springfield Primary ExaminerCarlton R. Croyle both of Assistant ExaminerRobert E. Garrett [73] Assignee: Westinghouse Electric Corporation, y Stratum et Pittsburgh, Pa.

[22] Filed: Dec. 9, 1971 [57] ABSTRACT P1 0 33 Gas turbine combustion apparatus in which the combustor is anchored at its upstream end and the transi- 52 us. c1. 60/3932 415/134 member is anchmd its dwmream 51 1111. c1 F02C 7/20 rold 9/04 kW/Stream end cmbustr and the uPStream [58] Field of Search 60/3932 3937- and member being disPSed mutual 285/164 165 302 319 415/134 engagement and alignment and freely slidable relation during thermal expansion by a clevis support structure [56] References Cited and sealed at their engaging portions by a slotted twin UNITED STATES PATENTS cuff 2,748,567 6/1956 Dougherty 60/39.37 ux 9 Claims, 8 Drawing Figures 54 r f' f 44b 1 441 52 55 55 47 45 446 44C i9 520 Q 1 I O O o 0 E i I 530 46 A 4 48 49 52b g; 20 i I A 68 k 22 76 H H H n H H 42 1 e Q 4o Patented Sept. 18, 1973 3,759,038

4 ShcetsSheet I FIG. I

Patented Sept. 18, 1973 3,759,038

4 Sheets-Sheet 4 1 SELF ALIGNING COMBUSTOR AND TRANSITION STRUCTURE FOR A GAS TURBINE BACKGROUND OF THE INVENTION Present high efficiency gas turbines require ever increasing operating temperature capabilities in order to minimize cost of operation and to extract the greatest amount of useful power from the fuel consumed. In such turbines the supporting and sealing structure of the combustion apparatus must be capable of accommodating higher temperatures without over-stressing associated components. Present apparatus of this type either does not permit the required thermal displacements without undesirable thermal stress or utilizes support walls that rob the components of the beneficial cooling effects of the pressurized compressor air dis charge.

This invention provides gas turbine combustion apparatus that permits combustor and transition member thermal displacement with a minimum of elastic and frictional restraint. In addition, the connection between the combustor and the associated transition member permits axial displacement of both the combustor and the transition member and limited radial displacement of the combustor at the connection, while restraining the transition member against radial displacement.

SUMMARY OF THE INVENTION Briefly, the present invention relates to gas turbine combustion apparatus of the type in which a plurality of combustors of the canister type are disposed in a plenum chamber and arranged in an annular array about the rotational axis of the rotor. Each combustor is anchored at its upstream end to the upstream wall of the outer casing and is telescopically connected at its downstream end by a slotted twin layer cuff spring to the upstream end of its associated transition member.

The transition member is supported by a Y-shaped yoke having its leg anchored to the compressor diffuser casing and its diverging arms straddling the transition member. Each of the arms carries a clevis member that slidably supports an associated clevis guide that is, in turn, attached to the transition member. The yoke restrains the transition member against movement in a plane normal to'the longitudinal axis of the combustor but permits axial movement. I

The cuff spring provides an annular seal between the transition member and the combustor that permits transverse as well as axial movement of the combustor to occur relative to the transition member. The cuff spring has two layers of springs to restrict leakage and to dampen vibrations, in operation, and is further formed with a back up ring to limit spring stress, and

spring catches to prevent pieces of the spring from entering the transition member in the event of breakage. The-transition mouth, i.e., the downstream end of the transition member, is locked and sealed to theturbine blade ring by an arrangement that prevents leakage therepast but permits some sliding relative thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a portion of an axial flow gas turbine showing fuel combustion apparatus having the invention incorporated therein;

FIG. 2 is an enlarged cross-sectional view taken on line II II of FIG. 1 and showing three of the combustor transition members with their associated support structure;

FIG. 3 is a cross-sectional view, similar to FIG. 2, but taken on a'still larger scale and showing only one of the combustor transition members;

FIG. 4 is a fragmentary view taken on line lVIV in FIG. 3 and showing one of the clevis assemblies;

FIG. 5 is an enlarged fragmentary sectional view showing the mouth or downstream end portion of one of the transition members and its locking structure;

FIG. 6 is a fragmentary perspective view of the mouth portions of two adjacent transition members;

FIG. 7 is a diametric axial sectional view of one of the cuff springs, and

FIG. 8 is an enlarged fragmentary sectional view showing the cuff spring in assembled and sealing relation with the combustor and transition member.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in detail, in FIG. 1 there is shown a radial sectional view of the central portion of a gas turbine power plant 10 having the invention incorporated therein. The gas turbine 10 is of the wellknown axial flow type comprising a multi-stage axial flow compressor portion 12, an axial flow turbine portion 14 and combustion apparatus 16.

The turbine 14 includes at least one motive fluid expansion stage including an annular row of stationary blades 18 disposed in a blade ring structure 20 and preceding an annular row of rotatable blades 21 carried by a turbine rotor 22.

The compressor 12 includes a plurality of air compressing stages, each stage comprising an annular row of rotatable blades 24 carried by a rotor 25 and preceding an annular row of stationary blades 26.

The compressor rotor 25 is drivenly connected to the turbine rotor 22 by a torque tube 28.

The combustion apparatus 16 includes a plurality of combustors 30 and associated transition members 31 arranged in an annular array concentric with the rotor aggregate (25, 22, 28). The combustors 30 are disposed in a plenum chamber 32 whose outer periphery is defined by outer casing or housing structure including a central tubular casing portion 33 and upstream and downstream casing portions 34 and 35. The inner periphery is defined generally by a portion of the com- .pressor casing structure 36 and 37, and by a tubular fairing structure, 39, 40 and 41 extending from the compressor casing structure 36 to the turbine blade ring 20. The fairing structure 39, 40, 41 encompasses the torque tube 28 and is anchored at its upstream end to the compressor casing 36 by the last row of stationary blades 26 and at its downstream end to the blade ring structure 20 by annular flange structure 42.

The fairing structure 39 also cooperates with the compressor casing structure 37 to form a diffuser structure having a passageway 43 diverging in the direction of flow of the compressed air from the compressor into the plenum chamber 32, as indicated by the arrow A.

A plurality of combustors 30 and associated transition members 31 are disposed in an equally spaced annular array, as indicated in FIG. 2; however, since they may all be substantially identical, only one will be described.

The combustor 30, as best shown in FIG. I, is of the stepped liner construction employing a plurality of cylindrical liners 44a-44f of graduated diameter disposed in axially spaced telescopic engagement with each other and defining a fuel combustion chamber 45 into which fuel from a suitable supply (not shown) is admit-- ted by a suitable fuel injection device 46 and ignited by an igniter 47.

To support the combustion of fuel, pressurized pri-- mary air is admitted from the plenum chamber 32 into the combustion chamber 45 by a plurality of apertures 48 in the liners 44a and 44b. In addition, secondary air is admitted through a plurality of apertures 49 in the last liner 44fto dilute the hot gaseous products of combustion to a temperature that the hot components of the turbine 14 can safely withstand.

The downstream end portion 51 of the last combustion liner 44f is disposed in internal telescopic engagement with the tubular upstream end portion 52 of the transition member 31. The end portion 52 is divided into two mating semi-cylindrical portions 52a and 52b bolted together at diametrically opposed mating flanges 53a and 53b (only one pair shown) by suitable bolts.

As best seen in FIGS. 1 and 8, the liner end portion 51 is of smaller diameter than the transition end portion 52 and is loosely received therein. Referring to FIG. 8, cuff spring 55 of annular shape comprising an inner segmented spring member 56 and an outer segmented spring member 57 is attached at one end 58 to the liner portion 51 and has its other end in spring biased relation with the inner wall surface of the transition end portion 52. The segments 57a of the outer spring member 57 are in peripherally staggered relation with the segments 56a of the inner spring members to provide a peripheral seal between the transition member and the combustor during operation.

A back-up ring member 59 having a radial, peripherally upstanding flange portion 60 is attached to the liner end portion 51 adjacent the free end portion of the cuff spring and positioned in radially spaced relation therewith during normal operation, but is so proportioned as to abut the inner spring 56 to limit deflection of the springs 56 and 57 during assembly, thereby to protect the cuff spring against excessive spring stress.

The outer spring segments 57a are provided with radially inwardly bent free end portions 61 extending beyond the flange 60 of the back-up ring (with regard to the fixed fulcrum point 58), so that should one of the segments 56a or 57a break away from the cuff spring, the broken segment will be prevented from entering the transition member 31 and being entrained in the motive gas flow. More specifically, should an outer segment 57a break away, movement of the bent end portion 61 to the right is arrested by abutment with the flange60. Should an inner segment 56a break away it is inherently held captive by the outer segments 574. Thus, broken segments 56a and/or 57a can cause no damage to the turbine blades.

The combustor and transition structure 30, 31 is supported intermediate its ends by a support structure 63. The support structure comprises a Y-shaped yoke member 64 having a pair of spaced divergent arms 65 ing the cuff spring 55 and the back-up ring member 59.

while the anchoring portion 68 extends across the diffusing passage 42 and is attached to the fairing member 41.

Referring to FIG. 3 the arms 65 of the yoke embrace a quadrant portion of the transition member within their bight 69 and are slidably attached to the transition member by a pair ofvclevis structures 70, one at each arm 65. The clevis structures are substantially identical and comprise a U-shaped male member 71 attached to the transition member 31 and a U-shaped female member 72 attached to the associated arm 65 at a right angle to the male member 71. The female member 72 has an open-ended groove 73 slidably embracing the central portion 74 of the male clevis member. As best seen in FIG. 4, the clevis permits left-to-right movement of the transition member, i.e., movement parallel to the transition members central longitudinal axis. Also, as best seen in FIG. 3, the clevis prevents or at least restricts movement in any direction in a plane normal to the central axis T of the transition member 31.

The transition member 31, as well known in the art, changes in cross-sectional shape from circular at its upstream or inlet end 52 to conform to the circular shape of the combustor 30, to arcuate at its downstream end or mouth 76. More particularly, the transition mouth 76, as best seen in FIG. 6 wherein two neighboring transition member mouths are shown in provided with a pair of circumferentially spaced radial walls 77 and 78 and a pair of radially spaced inner and outer arcuate walls 79 and 80.

The radial wall 77 is provided with three parallel ribs 77a, while the radial wall 78 is provided with two parallel ribs 780. The neighboring transition mouths 76 are disposed in close lateral relation with each other and the ribs 770 and 780 on adjacent walls 77 and 78 are spaced in complementary fashion to form an axial interlock therebetween. 1

The inner and outer arcuate walls 79 and 80 are provided with grooved members 79a and 80a (see FIGS. 5 and 6) which cooperate with mating flanged mem bers 82 and 83 retained by the fairing member flange 42 and the blade ring structure 20, respectively.

The transition mouth 76 is retained in assembled relation with the blade ring by a bracket 85 joined to the arcuate wall 80 by welding or the like and bolted to the blade ring 20 by suitable bolts 86.

It will now be apparent that the combustion apparatus 16 is provided with combustors 30 and associated transition members 31 that in operation may expand and elongate thermally with respect to each other and with respect to their anchoring means with a minimum of thermal stress, warpage and/or damage.

More particularly, the clevis structures 70 permit the transition members 31 to freely move in axial direction, i.e., towards the end casing wall 34 and/or towards the blade ring structure 20. The transition member mouths 76 are anchored to the blade ring structure 20 in the manner described above to permit radial and circumferentialexpansion while restricting blow by" of hot motive gases. g

In addition, the transition members 31 and the combustors 30 are supported at their free ends in a sturdy and reliable manner by the yoke support structure 63, while the combustors are maintained in sealing, yet freely movable, relation with their associated transition members 31 by the novel sealing arrangement compris- We claim:

1. A gas turbine comprising casing structure defining a plenum chamber,

a first motive expansion stage including a blade ring having a row of stationary blades and a rotor having a row of rotatable blades,

at least one fuel combustor disposed within said plenum chamber with its upstream end anchored to said casing structure, and effective to generate hot motive gases,

a transition member connected at its upstream end to the downstream end of said combustor and communicating at its downstream end with said first stage, and effective to transmit said gases to said first stage,

said transition member having its upstream end portion telescopically engaging the downstream end portion of said combustor in a manner to permit relative axial movement therebetween,

said transition member having its downstream end connected to said blade ring in a manner to restrain axial movement,

a support structure anchored to said casing structure and slidably supporting said transition member in a manner permitting movement parallel to its axis but restraining movement transverse thereto, and

an annular cuff spring interposed between the telescoping end portions of said transition member and said combustor,

said cuff spring comprising an inner segmented spring member and an outer segmented spring member, with said segments in peripherally staggered relation with each other to provide a peripheral seal between said transition member and said combustor during operation.

2. The structure recited in claim 1 in which one of the segmented spring members extends axially beyond the other and has its free end portions extending radially.

3. The structure recited in claim 1 in which the cuff spring is connected at one end to one of telescoping portions and has its other end in slidable abutment with the other of said telescoping portions, and

one of the telescoping portions having an annular radially extending stop portion in spaced relation with the cuff spring but engagable by the cuff spring during deflection thereof.

4. The structure recited in claim 1 in which the support structure comprises a yoke member having a pair of spaced arms, and

the transition member is disposed in the bight of said arms.

5. The structure recited in claim 4 in which the support structure further includes a leg portion extending radially inwardly,

the casing structure includes a tubular inner casing portion defining the plenum chamber in part, and

said leg portion is attached to said inner casing portion.

6. In a gas turbine power plant comprising an air compressor portion, an axial flow turbine portion, and combustion apparatus for generating hot motive combustion gases for motivating said turbine,

said turbine having a blade ring carrying a row of stationary blades and a rotor carrying a row of rotatable blades,

inner and outer casing structure defining an annular plenum chamber,

said combustion apparatus including an annular array of fuel combustors disposed in said plenum chamber with their upstream end portions attached to said outer casing,

each of said combustors having a transition member connected in axially slidable relation at its upstream end to the downstream end of its associated combustor and connected at its downstream end to said blade ring, whereby to conduct the hot motive gases from said combustor to said turbine,

a support structure carried by said inner casing and slidably supporting said transition member in a manner permitting movement parallel to its axis, but restraining movement transverse thereto,

said inner casing being concentric with the outer casing and having an annular portion for directing the pressurized air from the compressor to the plenum chamber,

said support structure comprising a yoke member having a pair of spaced arms and a leg member, said arms receiving the transition member within their bight, and

said leg member extending radially inward and being anchored to said annular portion.

7. The structure recited in claim 6 wherein the support structure further includes a clevis carried by. each of the arms,

said clevis having male and female members slidably associated with each other,

one of said clevis members being attached to the transition member,

the other of said clevis members being attached to the associated arm.

8. The structure recited in claim 6 in which each transition member has an arcuate mouth portion with circumferentially spaced radial walls at least partly defining an outlet for the motive gases, and

said radial walls have radial ribs so arranged that the mouth portions of neighboring transition members are keyed to each other.

9. The structure recited in claim 8 in which the mouth portion is further provided with radially spaced inner and outer arcuate walls cooperating with the radial walls to define the gas outlet, and

said arcuate walls having channel members for securing the mouth portion to the blade ring.

a: it a: 

1. A gas turbine comprising casing structure defining a plenum chamber, a first motive expansion stage including a blade ring having a row of stationary blades and a rotor having a row of rotatable blades, at least one fuel combustor disposed within said plenum chamber with its upstream end anchored to said casing structure, and effective to generate hot motive gases, a transition member connected at its upstream end to the downstream end of said combustor and communicating at its downstream end with said first stage, and effective to transmit said gases to said first stage, said transition member having its upstream end portion telescopically engaging the downstream end portion of said combustor in a manner to permit relative axial movement therebetween, said transition member having its downstream end connected to said blade ring in a manner to restrain axial movement, a support structure anchored to said casing structure and slidably supporting said transition member in a manner permitting movement parallel to its axis but restraining movement transverse thereto, and an annular cuff spring interposed between the telescoping end portions of said transition member and said combustor, said cuff spring comprising an inner segmented spring member and an outer segmented spring member, with said segments in peripherally staggered relation with each other to provide a peripheral seal between said transition member and said combustor during operation.
 2. The structure recited in claim 1 in which one of the segmented spring members extends axially beyond the other and has its free end portions extending radially.
 3. The structure recited in claim 1 in which the cuff spring is connected at one end to one of telescoping portions and has its other end in slidable abutment with the other of said telescoping portions, and one of the telescoping portions having an annular radially extending stop portion in spaced relation with the cuff spring but engagable by the cuff spring during deflection thereof.
 4. The structure recited in claim 1 in which the support structure comprises a yoke member having a pair of spaced arms, and the transition member is disposed in the bight of said arms.
 5. The structure recited in claim 4 in which the support structure further includes a leg portion extending radially inwardly, the casing structure includes a tubular inner casing portion defining the plenum chamber in part, and said leg portion is attached to said inner casing portion.
 6. In a gas turbine power plant comprising an air compressor portion, an axial flow turbine portion, and combustion apparatus for generating hot motive combustion gases for motivating said turbine, said turbine having a blade ring carrying a row of stationary blades and a rotor carrying a row of rotatable blades, inner and outer casing structure defining an annular plenum chamber, said combustion apparatus including an annular array of fuel combustors disposed in said plenum chamber with their upstream end portions attached to said outer casing, each of said combustors having a transition member connected in axially slidable relation at its upstream end to the downstream end of its associated combustor and connected at its downstream end to said blade ring, whereby to conduct the hot motive gases from said combustor to said turbine, a support structure carried by said inner casing and slidably supporting said transition member in a manner permitting movement parallel to its axis, but restraining movement transverse thereto, said inner casing being concentric with the outer casing and having an annular portion for directing the pressurized air from the compressor to the plenum chamber, said support structure comprising a yoke member having a pair of spaced arms and a leg member, said arms receiving the transition member within their bight, and said leg member extending radially inward and being anchored to said annular portion.
 7. The structure recited in claim 6 wherein the support structure further includes a clevis carried by each of the arms, said clevis having male and female members slidably associated with each other, one of said clevis members being attached to the transition member, the other of said clevis members being attached to the associated arm.
 8. The structure recited in claim 6 in which each transition member has an arcuate mouth portion with circumferentially spaced radial walls at least partly defining an outlet for the motive gases, and said radial walls have radial ribs so arranged that the mouth portions of neighboring transition members are keyed to each other.
 9. The structure recited in claim 8 in which the mouth portion is further provided with radially spaced inner and outer arcuate walls cooperating with the radial walls to define the gas outlet, and said arcuate walls having channel members for securing the mouth portion to the blade ring. 